I figured out what my problem is. There is an incompatibility between WP Google Analytics and Photo Dropper in WP 2.8.2. If WP Google Analytics is active Photo Dropper stops working. When I deactivate it, Photo Dropper works again. I hope the developers can resolve this issue.
I have the same problem. It was working fine yesterday but today when I click the search button nothing happens. Did you ever solve this issue?